Refactor commons code

Author: Gary Gregory

src/main/java/org/apache/commons/io/filefilter/AbstractFileFilter.java

@@ -23,6 +23,7 @@
 import java.nio.file.FileVisitResult;
 import java.nio.file.Path;
 import java.nio.file.attribute.BasicFileAttributes;
+import java.util.List;
 import java.util.Objects;
 
 import org.apache.commons.io.file.PathFilter;
@@ -97,6 +98,24 @@ public boolean accept(final File dir, final String name) {
         return accept(new File(dir, name));
     }
 
+    void append(final List<?> list, final StringBuilder buffer) {
+        for (int i = 0; i < list.size(); i++) {
+            if (i > 0) {
+                buffer.append(",");
+            }
+            buffer.append(list.get(i));
+        }
+    }
+
+    void append(final Object[] array, final StringBuilder buffer) {
+        for (int i = 0; i < array.length; i++) {
+            if (i > 0) {
+                buffer.append(",");
+            }
+            buffer.append(array[i]);
+        }
+    }
+
     /**
      * Handles exceptions caught while accepting.
      *

src/main/java/org/apache/commons/io/filefilter/AndFileFilter.java

@@ -215,12 +215,7 @@ public String toString() {
         final StringBuilder buffer = new StringBuilder();
         buffer.append(super.toString());
         buffer.append("(");
-        for (int i = 0; i < fileFilters.size(); i++) {
-            if (i > 0) {
-                buffer.append(",");
-            }
-            buffer.append(fileFilters.get(i));
-        }
+        append(fileFilters, buffer);
         buffer.append(")");
         return buffer.toString();
     }

src/main/java/org/apache/commons/io/filefilter/NameFileFilter.java

@@ -207,14 +207,7 @@ public String toString() {
         final StringBuilder buffer = new StringBuilder();
         buffer.append(super.toString());
         buffer.append("(");
-        if (names != null) {
-            for (int i = 0; i < names.length; i++) {
-                if (i > 0) {
-                    buffer.append(",");
-                }
-                buffer.append(names[i]);
-            }
-        }
+        append(names, buffer);
         buffer.append(")");
         return buffer.toString();
     }

src/main/java/org/apache/commons/io/filefilter/OrFileFilter.java

@@ -196,14 +196,7 @@ public String toString() {
         final StringBuilder buffer = new StringBuilder();
         buffer.append(super.toString());
         buffer.append("(");
-        if (fileFilters != null) {
-            for (int i = 0; i < fileFilters.size(); i++) {
-                if (i > 0) {
-                    buffer.append(",");
-                }
-                buffer.append(fileFilters.get(i));
-            }
-        }
+        append(fileFilters, buffer);
         buffer.append(")");
         return buffer.toString();
     }

src/main/java/org/apache/commons/io/filefilter/PrefixFileFilter.java

@@ -209,14 +209,7 @@ public String toString() {
         final StringBuilder buffer = new StringBuilder();
         buffer.append(super.toString());
         buffer.append("(");
-        if (prefixes != null) {
-            for (int i = 0; i < prefixes.length; i++) {
-                if (i > 0) {
-                    buffer.append(",");
-                }
-                buffer.append(prefixes[i]);
-            }
-        }
+        append(prefixes, buffer);
         buffer.append(")");
         return buffer.toString();
     }

src/main/java/org/apache/commons/io/filefilter/SuffixFileFilter.java

@@ -209,14 +209,7 @@ public String toString() {
         final StringBuilder buffer = new StringBuilder();
         buffer.append(super.toString());
         buffer.append("(");
-        if (suffixes != null) {
-            for (int i = 0; i < suffixes.length; i++) {
-                if (i > 0) {
-                    buffer.append(",");
-                }
-                buffer.append(suffixes[i]);
-            }
-        }
+        append(suffixes, buffer);
         buffer.append(")");
         return buffer.toString();
     }

src/main/java/org/apache/commons/io/filefilter/WildcardFileFilter.java

@@ -209,14 +209,8 @@ public String toString() {
         final StringBuilder buffer = new StringBuilder();
         buffer.append(super.toString());
         buffer.append("(");
-        for (int i = 0; i < wildcards.length; i++) {
-            if (i > 0) {
-                buffer.append(",");
-            }
-            buffer.append(wildcards[i]);
-        }
+        append(wildcards, buffer);
         buffer.append(")");
         return buffer.toString();
     }
-
 }